Koi Care Guide
Cyprinus carpio · Freshwater Fish
What Koi look like
Koi are domesticated ornamental common carp with long powerful bodies and paired barbels at the mouth. They are much larger and more muscular than goldfish, with a single tail and many selectively bred color patterns.
Behavior & temperament
Koi are social, peaceful, highly active pond fish that constantly cruise, graze, and root through substrate. Their adult size, waste load, digging behavior, and long lifespan make them unsuitable for ordinary aquariums. They need deep, filtered outdoor ponds with excellent oxygen and predator protection.
Diet & feeding
Koi are omnivorous carp that graze algae, plant matter, insect larvae, worms, crustaceans, and detritus. In captivity, feed quality koi pellets matched to season and water temperature, with supplemental greens and occasional protein treats. Avoid heavy feeding in cold water because digestion slows.
Behind the name
Koi is the Japanese common name for carp; Cyprinus is the classical carp name and carpio refers to common carp.
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Koi?
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